--- gcc/config/tm-hp9k320.h	2018/04/24 16:53:28	1.1
+++ gcc/config/tm-hp9k320.h	2018/04/24 16:55:12	1.1.1.2
@@ -101,7 +101,7 @@ the Free Software Foundation, 675 Mass A
 /* These are the ones defined by HPUX cc, plus mc68000 for uniformity with
    GCC on other 68000 systems.  */
 
-#define CPP_PREDEFINES "-Dhp9000s200 -Dhp9000s300 -DPWB -Dhpux -Dunix"
+#define CPP_PREDEFINES "-Dhp9000s200 -Dhp9000s300 -DPWB -Dhpux -Dunix -D__hp9000s300 -D_HPUX_SOURCE"
 
 /* Every structure or union's size must be a multiple of 2 bytes.  */